INSYS GSM 4.3 I4, Manual

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Functions INSYS GSM 4.3 I4
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11.17 Alarm Inputs
The INSYS GSM 4.3 I4 has four digital inputs, which can trigger an “alarm” when con-
nected to GND. When an alarm occurs, the INSYS GSM 4.3 I4 can send a message either
via a data connection or SMS, or establish a voice connection.
The INSYS GSM 4.3 I4 will evaluate a connection of the input to GND as a pulse. This will
only consider a falling edge. Two “pulse types” are available: “simple pulses” and “count
pulses”, i.e. a pulse sequence. If no rising edge is detected for at least 4 seconds, a “simple
alarm” is processed. The INSYS GSM 4.3 I4 can react on this event with the dispatch of a
single message or the establishment of a voice connection. “Count pulses” are periodic
connections to GND, which do not last longer than two seconds. The length of a pulse or
the pause respectively can have a duration between 0.3 and 2 seconds. The complete
evaluation of several pulses is performed after a pause of 5 seconds (refer to Figure 6
Duration of inter-pulse periods). Depending on the number of count pulses, the INSYS
GSM 4.3 I4 addresses the messages 1 to 10 and sends it to the respective recipients. Up
to 5 alarms are buffered at the inputs and processed consecutively.
Figure 6 Duration of inter-pulse periods
The sent messages consist of the collective message and the according message 1 to 10.
It is thus possible to specify the system with the collective message and to specify the
reported system part in the pulse message. Moreover, a message can be sent to up to 20
recipients.
For control purposes, simple and pulse alarms may be triggered via AT commands. The
status of the alarm inputs can be queried by AT commands or via DTMF tones.
Configuration with AT commands
In order to request the input states, use the
command
AT**IN?